The present invention relates to field communication distribution equipment and, more particularly, to improvements in cables for such equipment to increase data throughput of such cables without increasing cross-talk and other interference between data communication channels between the distribution equipment.
The J-1077 A/U distribution box (hereinafter referred to simply as the “J-1077”) is used to interconnect military field telephones and other communication devices in mobile, transportable, and semi-permanent installations. The J-1077 has provisions for connection of one or two 26 conductor-pair cables to a set of 26 pairs of spring post connectors mounted on a panel within the box. The standard cable for use with J-1077 type boxes is designated CX-4566 A/G. As such, the J-1077 can interconnect two 26-pair cables or can terminate a single 26-pair cable and provide connections to the conductors within the cable, such as for telephone sets or test equipment. The J-1077 has been in use for several decades and has proved to be generally rugged and reliable in varied field conditions. Additional information about the J-1077 distribution box can be obtained from Associated Industries of North Hollywood, Calif. (www.associated-ind.com) and from other sources.
Although generally successful, the J-1077 has some shortcomings. The configuration of the spring post connectors requires that wires be stripped before insertion into the posts. Stripping sometimes damages some of the strands of a conductor, causing them to break off, thereby reducing the signal carrying capability of the conductor. Stripping is also time-consuming if a large number of connections need to be made at one time.
Another problem with the J-1077 is that if a communication malfunction occurs in a system using J-1077 distribution boxes and cables, it is often difficult and time-consuming to isolate the problem among the possible 26 circuits which may be in use. At present, the usual procedure is to disconnect and reconnect each wire until the problem is isolated. A related problem is detecting the location of a break or cut in the cable or unauthorized connections to the network, such as by an enemy. Additionally, there are no provisions on a standard J-1077 box for connection of computers thereto to enable field networking of computers or data communication between computerized devices using the J-1077 system.
Some types of military communication equipment have optical data signal interfaces which utilize optical fiber communication media. Optical data signals have a number of advantages in military applications, including high efficiency over long distances, high data rates, difficulty of tapping by an enemy, and the like. There is also a need for converting signals carried by optical fiber media to electrical data signals for carriage by conventional copper based cables.
The J-1077 distribution box and the standard CX-4566 A/G cable, were originally designed for carrying multiple channels of audio frequency telephone signals. As stated above, military field communications have evolved beyond voice and teletype communications to high speed data communications for text, numeric, and image data in addition to voice signals. It is desirable that such communications be carried on using standard data communication protocols to enable existing equipment and devices to be used to thereby avoid the expense need for designing